Three adults and two juveniles were found dead in two Minnesota homes in what police believe was a quadruple murder-suicide.

According to a press release from the Duluth Police Department, officers arrived at a home in the 6000 block of Tacony Street in Duluth around 2 p.m. on Thursday, November 7, after one of the resident’s co-workers reported that she had not shown up for work. Erin Abramson, 47, and her son Jacob Nephew, 15, were found dead inside from gunshot wounds, police said.

Authorities quickly identified Anthony Nephew, 46 — Abramson’s ex and Jacob’s father — as a suspect and set up surveillance at his home, located in the 4400 block of West 6th Street, about 1 mile from original crime scene.

Duluth Police Chief Mike Ceynowa told a press conference on Friday, November 8 that police used a drone to enter the home, where they found the bodies of Anthony’s ex-wife, Kathryn Nephew, 45, and her son Oliver Nephew, 7. They also died from gunshot wounds, police said.

Anthony was also found dead in the second home “from what appears to be a self-inflicted gunshot wound,” according to police.

Authorities have not yet confirmed a motive for the shooting.

Ceynowa said Anthony had a history of mental health issues and police were called to the West 6th Street home several times. He also added that investigators were still using cellphone data to establish when the shootings took place.

“Our thoughts and prayers are with the family, friends and loved ones of the four victims of this tragic incident,” the chief said. “We also want to extend our condolences to the Duluth community and the Superior community as this is a senseless and tragic event.”

Police said there was no threat to the public and the investigation was ongoing.

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Minnesota Public Radio reported that Duluth Public Schools — where Oliver was a first-grader — has sent a message to parents about the incident and is providing students with crisis resources.

“This is not something that happens often in our community,” Duluth Mayor Roger Reinert said, according to Minnesota Public Radio. “It’s been a few years since we’ve seen something like this, and we’re going to mourn, but we’re also going to make sure we support these families and support our public safety team.”

If you are a victim of domestic violence, call the National Domestic Violence Hotline at 1-800-799-7233 or go to thehotline.org. All calls are free and confidential. The hotline is available 24/7 in more than 170 languages.